<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <style>
    .wrap{
      width: 500px;
      height: 600px;
      background: #ccc;
    }
    .left{
      width: 200px;
      height: 400px;
      background: red;
      float: left;
    }
.content{
  height: 450px;
  background: seagreen;
  overflow: hidden;
}
    .right{
      width: 150px;
      height: 350px;
      background: blue;
      /* overflow: hidden; */
      float: right;
    }
  </style>
</head>
<body>
  <div class="wrap">
    <div class="left"></div>
    <div class="content"></div>
    <div class="right"></div>
  </div>
</body>
</html>
<!-- 
  三栏布局
    写法类似与两栏布局，中间部分写在最后
 -->